6-[(2,4-diaminophenyl)azo]-3-[[4-[[4-[[7-[(2,4-diaminophenyl)azo]-1-hydroxy-3-sulpho-2-naphthyl]azo]phenyl]amino]-3-sulphophenyl]azo]-4-hydroxynaphthalene-2-sulphonic acid

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: screening tests

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with limited documentation / justification

Justification for type of information:

The supporting QMRF report has been attached

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I))

Principles of method if other than guideline:

The data is predicted using the OECD QSAR toolbox version 3.3 with logKow as the primary descriptor.

GLP compliance:

not specified

Specific details on test material used for the study:

- Name of test material : 6-[(2,4-diaminophenyl)azo]-3-[[4-[[4-[[7-[(2,4-diaminophenyl)azo]-1-hydroxy-3-sulpho-2-naphthyl]azo]phenyl]amino]-3-sulphophenyl]azo]-4-hydroxynaphthalene-2-sulphonic acid
- Molecular formula : C44H35N13O11S3
- Molecular weight : 1018.0385 g/mol
- Smiles notation : c1cc(ccc1Nc2ccc(cc2S(=O)(=O)O)/N=N/c3c(cc4ccc(cc4c3O)/N=N/c5ccc(cc5N)N)S(=O)(=O)O)/N=N/c6c(cc7ccc(cc7c6O)/N=N/c8ccc(cc8N)N)S(=O)(=O)O
- InChl : 1S/C44H35N13O11S3/c45-24-3-12-35(33(47)17-24)54-51-28-5-1-22-15-39(70(63,64)65)41(43(58)31(22)19-28)56-50-27-9-7-26(8-10-27)49-37-14-11-30(21-38(37)69(60,61)62)53-57-42-40(71(66,67)68)16-23-2-6-29(20-32(23)44(42)59)52-55-36-13-4-25(46)18-34(36)48/h1-21,49,58-59H,45-48H2,(H,60,61,62)(H,63,64,65)(H,66,67,68)/b54-51+,55-52+,56-50+,57-53+
- Substance type : Organic
- Physical state : Solid

Oxygen conditions:

aerobic

Inoculum or test system:

other: Microorganisms

Duration of test (contact time):

28 d

Based on:

not specified

Parameter followed for biodegradation estimation:

other: BOD

Key result

Parameter:

other: BOD

Value:

0.2

Sampling time:

28 d

Remarks on result:

other: Other details not known

Details on results:

Test substance undergoes 0.2% degradation by BOD in 28 days.

The prediction was based on dataset comprised from the following descriptors: BOD
Estimation method: Takes average value from the 10 nearest neighbours
Domain  logical expression:Result: In Domain

((((((((("a" or "b" or "c" or "d" )  and "e" )  and "f" )  and "g" )  and "h" )  and "i" )  and ("j" and ( not "k") )  )  and "l" )  and ("m" and "n" )  )

Domain logical expression index: "a"

Referential boundary: The target chemical should be classified as Amine OR Aromatic compound OR Azo compound OR Hydroxy compound OR Phenol OR Primary amine OR Primary aromatic amine OR Secondary amine OR Secondary aromatic amine OR Sulfonic acid OR Sulfonic acid derivative by Organic functional groups, Norbert Haider (checkmol) ONLY

Domain logical expression index: "b"

Referential boundary: The target chemical should be classified as Alcohol, olefinic attach [-OH] OR Aliphatic Nitrogen, one aromatic attach [-N] OR Aliphatic Nitrogen, two aromatic attach [-N-] OR Aromatic Carbon [C] OR Azo [-N=N-] OR Hydroxy, aromatic attach [-OH] OR Hydroxy, sulfur attach [-OH] OR Miscellaneous sulfide (=S) or oxide (=O) OR Nitrogen, two or tree olefinic attach [>N-] OR Olefinic carbon [=CH- or =C<] OR Oxygen, one aromatic attach [-O-] OR Suflur {v+4} or {v+6} OR Sulfinic acid [-S(=O)OH] OR Sulfonate, aromatic attach [-SO2-O] by Organic functional groups (US EPA) ONLY

Domain logical expression index: "c"

Referential boundary: The target chemical should be classified as Aminoaniline, meta OR Aromatic amine OR Aryl OR Azo OR Fused carbocyclic aromatic OR Overlapping groups OR Phenol OR Sulfonic acid by Organic Functional groups (nested) ONLY

Domain logical expression index: "d"

Referential boundary: The target chemical should be classified as Aminoaniline, meta OR Aniline OR Aromatic amine OR Aryl OR Azo OR Fused carbocyclic aromatic OR Naphtalene OR Phenol OR Sulfonic acid by Organic Functional groups ONLY

Domain logical expression index: "e"

Referential boundary: The target chemical should be classified as Not calculated by Biodeg BioHC half-life (Biowin) ONLY

Domain logical expression index: "f"

Referential boundary: The target chemical should be classified as Does NOT Biodegrade Fast by Biodeg probability (Biowin 1) ONLY

Domain logical expression index: "g"

Referential boundary: The target chemical should be classified as Not calculated by Hydrolysis half-life (Ka, pH 7)(Hydrowin) ONLY

Domain logical expression index: "h"

Referential boundary: The target chemical should be classified as Not calculated by Hydrolysis half-life (pH 6.5-7.4) ONLY

Domain logical expression index: "i"

Referential boundary: The target chemical should be classified as Class 5 (Not possible to classify according to these rules) by Acute aquatic toxicity classification by Verhaar (Modified) ONLY

Domain logical expression index: "j"

Referential boundary: The target chemical should be classified as No alert found by Carcinogenicity (genotox and nongenotox) alerts by ISS

Domain logical expression index: "k"

Referential boundary: The target chemical should be classified as Aromatic diazo (Genotox) OR Aromatic mono-and dialkylamine (Genotox) OR Benzenesulfonic ethers, methylation (Nongenotox) OR Hydrazine (Genotox) OR Primary aromatic amine,hydroxyl amine and its derived esters (Genotox) OR Structural alert for genotoxic carcinogenicity OR Structural alert for nongenotoxic carcinogenicity by Carcinogenicity (genotox and nongenotox) alerts by ISS

Domain logical expression index: "l"

Referential boundary: The target chemical should be classified as Not bioavailable by Lipinski Rule Oasis ONLY

Domain logical expression index: "m"

Parametric boundary:The target chemical should have a value of log BCF max which is >= 0.958 log(L/kg wet)

Domain logical expression index: "n"

Parametric boundary:The target chemical should have a value of log BCF max which is <= 4.49 log(L/kg wet)

Validity criteria fulfilled:

not specified

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

The test chemical 6-[(2,4-diaminophenyl)azo]-3-[[4-[[4-[[7-[(2,4-diaminophenyl)azo]-1-hydroxy-3-sulpho-2-naphthyl]azo]phenyl]amino]-3-sulphophenyl]azo]-4-hydroxynaphthalene-2-sulphonic acid was estimated to be not readily biodegradable in water.

Executive summary:

Biodegradability of 6 -[(2,4 -diaminophenyl)azo]-3 -[[4 -[[4 -[[7 -[(2,4 -diaminophenyl)azo]-1 -hydroxy-3 -sulpho-2 -naphthyl]azo]phenyl]amino]-3 -sulphophenyl]azo]-4 -hydroxynaphthalene-2 -sulphonic acid (CAS no. 76186 -07 -7) is predicted using QSAR toolbox version 3.3 with logKow as the primary descriptor. Test substance undergoes 0.2% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical 6 -[(2,4 -diaminophenyl)azo]-3 -[[4 -[[4 -[[7 -[(2,4 -diaminophenyl)azo]-1 -hydroxy-3 -sulpho-2 -naphthyl]azo]phenyl]amino]-3 -sulphophenyl]azo]-4 -hydroxynaphthalene-2 -sulphonic acid was estimated to be not readily biodegradable in water.

Description of key information

Biodegradability of 6 -[(2,4 -diaminophenyl)azo]-3 -[[4 -[[4 -[[7 -[(2,4 -diaminophenyl)azo]-1 -hydroxy-3 -sulpho-2 -naphthyl]azo]phenyl]amino]-3 -sulphophenyl]azo]-4 -hydroxynaphthalene-2 -sulphonic acid (CAS no. 76186 -07 -7) is predicted using QSAR toolbox version 3.3 (2017) with logKow as the primary descriptor. Test substance undergoes 0.2% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical 6 -[(2,4 -diaminophenyl)azo]-3 -[[4 -[[4 -[[7 -[(2,4 -diaminophenyl)azo]-1 -hydroxy-3 -sulpho-2 -naphthyl]azo]phenyl]amino]-3 -sulphophenyl]azo]-4 -hydroxynaphthalene-2 -sulphonic acid was estimated to be not readily biodegradable in water.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Additional information

Various predicted data for the target compound 6 -[(2,4 -diaminophenyl)azo]-3 -[[4 -[[4 -[[7 -[(2,4 -diaminophenyl)azo]-1 -hydroxy-3 -sulpho-2 -naphthyl]azo]phenyl]amino]-3 -sulphophenyl] azo]-4 -hydroxynaphthalene-2 -sulphonic acid (CAS No. 76186-07-7) and supporting weight of evidence studies for its structurally similar read across substance were reviewed for the biodegradation end point which are summarized as below:

 

In a prediction done by SSS (2017) using OECD QSAR toolbox version 3.3 with logKow as the primary descriptor, percentage biodegradability of test chemical6-[(2,4-diaminophenyl)azo]-3-[[4-[[4-[[7-[(2,4-diaminophenyl)azo]-1-hydroxy-3-sulpho-2-naphthyl]azo]phenyl]amino]-3-sulphophenyl]azo]-4-hydroxynaphthalene-2-sulphonic acid(CAS No. 76186-07-7) was estimated.Test substance undergoes 0.2% degradation by BOD in 28 days. Thus, based on percentage degradation, the test chemical6-[(2,4-diaminophenyl)azo]-3-[[4-[[4-[[7-[(2,4-diaminophenyl)azo]-1-hydroxy-3-sulpho-2-naphthyl]azo]phenyl]amino]-3-sulphophenyl]azo]-4-hydroxynaphthalene-2-sulphonic acidwas estimated to be not readily biodegradable in water.

 

In another prediction using the Estimation Programs Interface Suite (EPI suite, 2017), the biodegradation potential of the test compound 6 -[(2,4 -diaminophenyl)azo]-3 -[[4 -[[4 -[[7 -[(2,4 -diaminophenyl)azo]-1 -hydroxy-3 -sulpho-2 -naphthyl]azo]phenyl]amino]-3-sulphophenyl]azo]-4-hydroxynaphthalene-2-sulphonic acid(CAS No. 76186-07-7) in the presence of mixed populations of environmental microorganisms was estimated.The biodegradability of the substance was calculated using seven different models such as Linear Model, Non-Linear Model, Ultimate Biodegradation Timeframe, Primary Biodegradation Timeframe, MITI Linear Model, MITI Non-Linear Model and Anaerobic Model (called as Biowin 1-7, respectively) of the BIOWIN v4.10 software. The results indicate that chemical 6 -[(2,4 -diaminophenyl)azo]-3 -[[4 -[[4 -[[7 -[(2,4 -diaminophenyl)azo]-1 -hydroxy-3 -sulpho-2 -naphthyl]azo]phenyl]amino]-3 -sulphophenyl]azo]-4 -hydroxynaphthalene-2 -sulphonic acid is expected to be not readily biodegradable.

 

In a supporting weight of evidence study from peer reviewed journal (U. Pagga and O. Brown; 1986) for the read across chemical disodium 7 -amino-4 -hydroxy-3 -[(E)-2 -(4 -{4 -[(E)-2 -(1 -hydroxy-4 -sulfonatonaphthalen-2 -yl)diazen-1 -yl]-3 -methoxyphenyl}-2-methoxyphenyl)diazen-1-yl]naphthalene-2-sulfonate (CAS no. 6449-35-0),biodegradation experiment was carried out for 42 days for evaluating the percentage biodegradation of the read across chemical disodium 7 -amino-4 -hydroxy-3 -[(E)-2 -(4 -{4 -[(E)-2 -(1 -hydroxy-4 -sulfonatonaphthalen-2 -yl)diazen-1 -yl]-3 -methoxyphenyl}-2 -methoxyphenyl)diazen-1 -yl]naphthalene-2-sulfonate using modified OECD Guideline 302B. Activated sludge was used as a test inoculum. The sources of the activated sludge were treatment plants conveniently located to the laboratories carrying out the test. These treatment plants received communal and/or industrial wastewater. Concentration of inoculum i.e, activated sludge used was 0.5 g/l and initial test substance conc. used in the study was 100 mg/l. Analytical methods involve the measurement of extinction at absorption maximum 412 nm and DOC (dissolved organic carbon).The percentage degradation of the test substance disodium 7 -amino-4 -hydroxy-3 -[(E)-2 -(4 -{4 -[(E)-2 -(1 -hydroxy-4 -sulfonatonaphthalen-2 -yl)diazen-1 -yl]-3 -methoxyphenyl}-2 -methoxyphenyl)diazen-1 -yl]naphthalene-2 -sulfonate was determined to be 44% by using DOC removal parameter in 42 days. Thus, based on percentage degradation, the chemical disodium 7 -amino-4 -hydroxy-3 -[(E)-2 -(4 -{4 -[(E)-2 -(1 -hydroxy-4 -sulfonatonaphthalen-2 -yl)diazen-1 -yl]-3 -methoxyphenyl}-2 -methoxyphenyl)diazen-1 -yl]naphthalene-2 -sulfonate was considered to be not readily biodegradable in nature.

 

For the read across chemical Tetrasodium 3,3'-[(3,3'-dimethoxy[1,1'-biphenyl]-4,4'-diyl)bis(azo)]bis[5-amino-4-hydroxynaphthalene-2,7-disulphonate] (CAS no. 2429-74-5) from authoritative database (J-CHECK and HSDB, 2017), biodegradation study was conducted for 28 days for evaluating the percentage biodegradability of read across substance Tetrasodium 3,3'-[(3,3'-dimethoxy[1,1'-biphenyl]-4,4'-diyl)bis(azo) ]bis[5 -amino-4 -hydroxynaphthalene-2,7 -disulphonate]. The study was performed according to OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I)) under aerobic conditions. Concentration of inoculum i.e, sludge used was 30 mg/l and initial test substance conc. used in the study was 100 mg/l, respectively. The percentage degradation of substance Tetrasodium 3,3'-[(3,3'-dimethoxy[1,1'-biphenyl]-4,4'-diyl)bis(azo)]bis[5-amino-4-hydroxynaphthalene-2,7-disulphonate] was determined to be 4, 1 and 2% by BOD, TOC removal and HPLC parameter in 28 days. Thus, based on percentage degradation, Tetrasodium 3,3'-[(3,3'-dimethoxy[1,1'-biphenyl] -4,4'-diyl)bis(azo)] bis[5-amino-4-hydroxynaphthalene-2,7-disulphonate] is considered to be not readily biodegradable in nature.

 

On the basis of above results for target chemical 6 -[(2,4 -diaminophenyl)azo]-3 -[[4 -[[4 -[[7 -[(2,4 -diaminophenyl)azo]-1 -hydroxy-3 -sulpho-2 -naphthyl]azo]phenyl]amino]-3 -sulpho phenyl]azo]-4 -hydroxynaphthalene-2 -sulphonic acid(from OECD QSAR toolbox version 3.3 and EPI suite, 2017) and for its read across substance (from peer reviewed journal and authoritative database J-CHECK & HSDB), it can be concluded that the test substance 6 -[(2,4 -diaminophenyl)azo]-3 -[[4 -[[4 -[[7 -[(2,4 -diaminophenyl)azo]-1 -hydroxy-3 -sulpho-2 -naphthyl]azo]phenyl]amino]-3 -sulphophenyl]azo]-4 -hydroxynaphthalene-2 -sulphonic acid can be expected to be not readily biodegradable in nature.